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What types of radiation are emitted from the waste from nuclear power stations? (eg alpha, beta, gamma, neutrons etc.) Why can this not be put to use to recycle? Or is the cost of re-use greater that that of diposal? Presumably the radiation is energy?

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Radiation is energy emitted from certain bodies, such as uranium. Marie Courie was the first in finding this out in uranium during the early 20th century and she died of cancer due to her experiments.

Not all radiations cause cancer, though. There are, basically, two types: inonizing and non-ionizing radiations. The latter are emitted by household devices, such as microwave, television or radio. They don’t have any proved harmful effect in the body.

Radiations emitted by the materials used in nuclear stations to produce electricity (uranium and its by products, neptune and pluton) are, on the contrary, ionizing. This means that when they cross our bodies, they can alter our DNA, the material which constitutes our genes. Such alterations are the cause of cancer and other potential health hazards caused by these radiations.

The materials with which nuclear stations work take thousands of years to lose their radioactive power. This means that the only way to dispose them is storing them in an ultra-safe nuclear waste wharehouse. Deciding where to locate such wharehouses creates social problems (would you like to have one close to your town?), apart from being only a partial solution, since the production of waste in many countries overcomes the storage capacity.

Nuclear power stations rely on thermal (heat) energy released by nuclear reactions in the fuel. As sufficiently pure fuel is brought together in large enough quantities a large amount of heat is generated through these reactions.

This heat is then used in the same way as heat from burning coal – it boils water and the steam then drives a turbine which drives a generator.

As a by-product of this process nuclear radiation is also given off. Depending on the exact type of fuel it will be a varying mix of alpha, beta and gamma particles (the neutrons released by Uranium-235 decay are used to split further atoms). However, although this radiation does indeed contain energy harnessing it is somewhat more problematic.

Firstly, the heat of the reactor precludes harnessing alpha or beta particles since the heat-proofing will absorb them. Gamma rays could potentially be harnessed, but the trouble is that they pass straight through most matter without passing on their energy – this is why extremely dense materials such as lead are needed to stop them.

There is some good news though. Spent nuclear fuel still contains a large amount of un-used fuel. This can be re-processed and put back into the reactor.

Eventually we are left with waste, which will stay radioactive for centuries. Again, alpha and beta particles are too easily stopped to really be of much use. The gamma rays, again, are rather too difficult to absorb practically.

Still, your idea is interesting. Perhaps in the future something similar to a photovoltaic cell (which uses lower-frequency electromagnetic radiation) could be used to harness that energy. Quick; patent it :)

Oh dear. There is such a lack of common knowledge about nuclear radiation and the problems of nuclear waste. The trouble is that there has been such a panic since TMI and Chernoble that the media, Greens and their Friends have to scream danger or risk being ostracised. Let’s introduce a little effort into thinking about the physics and the myths.

1. Much of the useful energy in a thermal reactor comes from slowing down the fast neutrons to thermal speeds in the moderator because slow neutrons are then more likely to perpetuate the chain reactions. The moderator and/or its shielding will absorb the alpha and beta radiation as well and pass it all to the electrical generation cycle.

2. Less than 5 percent of the possible energy from energy output from uranium/plutonium fuel is extracted in the first charging cycle because the reaction products absorb too many neutrons and deplete the numbers available for further chain reactions. The nuclear waste still contains a lot of unburnt fuel which could be recycled – but we don’t do this at the moment. This is one reason why we must store the waste until we have the capability to retrieve and reprocess it.

3. That waste has a huge amount of potential energy stored in it. For example, all the plutonium that could have been used to make bombs could be consumed in a nuclear reactor in a controlled way to release all the energy slowly to provide electricity for many centuries.

4. The long half-life components of nuclear waste that might last for centuries only decay very slowly – so aren’t highly radioactive. It’s the short half-life products that are highly active but don’t stay around for long.

5. It is possible to de-activate nuclear waste by transmutation. There are designs for a transmuter reactor in which a high neutron flux can transmute a long-life element into a short-life isotope or daughter elements. In 2006 the Central Laser Facility at the Rutherford Laboratory reported that it had transmuted some radioactive iodine with a half-life of thousands of years into an isotope with a half-life of a few-hours. We are not stuck with a guilty legacy of leaving a world full of toxic waste for our descendants – just a legacy of frightening students away from the study of physics and nuclear engineering.

There are more than three pages of different kinds of artificial
radioactive elements produced at a nuclear power plant. Far more than are tested in lab samples or with dosimeters at the fenceline.
Most only produce an infinitesimal amount of radioactivity. However
radioactivity doses are cumulative. And according to the American
Academy of science in the BIOLOGICAL EFFECTS OF IONIZING
RADIATION report there is no amount however infinitesimal which
does not effect cell growth. Cell growth outside of its intended
growth path is CANCER. This report only underscored the same info
from Pr.Dr. Muller who won the Nobel Prize in medicine in1947.
Marie Curie who discovered the properties of Radium died of Cancer and her daughter who discovered artificial radioactivity
also died of cancer. WHEN WILL WE EVER LEARN ?